Several diseases are thought to be caused by the abnormal folding and aggregation of disease-specific proteins. These proteins can accumulate into pathologically diagnostic accumulations, known as amyloids, which are visualized by certain histologic stains. Amyloids are thought to elicit inflammatory responses and have multiple negative consequences for the involved tissues. In addition, smaller aggregates of abnormally folded protein may exist and exert cytotoxic effects.
Transthyretin (TTR) is one of the many proteins that are known to misfold and aggregate (e.g., undergo amyloidogenesis). Transthyretin-related amyloidosis encompasses two forms of disease: familial disease arising from misfolding of a mutated or variant TTR, and a sporadic, non-genetic disease caused by misaggregation of wild-type TTR. The process of TTR amyloidogenesis can cause pathology in the nervous system and/or heart, as well as in other tissues.